Induction-meter structure



Feb. 4, 1930. A. CALLSEN 1,745,842

INDUCTION METER STRUCTURE Filed Jan. 6, 1937 WITNESSES:

INVENTOR I 54 fi/berf Caflsen,

Patented Feb. 4, 1930 UNITED STATES PATEN OFFICE ALBERT CALLSEN, OFNUREMBERG, GERMANY,'ASSIGNOR.TO WESTINGHOUSE ELECTRIC & MANUFACTURINGCOMPANY, A OORPORATIONOF PENNSYLVANIA INDUCTION-METER srnnoriiitnApplication filed January 6, 1927, Serial No. 159,456, and Germany March29, 1926.

My invention relates to induction watthour meters and more particularlyto core structures for such meters.

My invention has for its object to provide 7 a core structure forwatt-hour meters that shall be characterized by mechanical rigidity.

A further object of my invention is to provide an induction meter thatshall be free from frequency noises.

In present meter practice, it is common to provide a magnetic shunt forthe series core for correcting the upper part of the registration-loadcurve. The principle on which this shunt operates is well known to thoseskilled in the art.

' In practicing my invention, I employ a structure comprising a magneticshunt that is an extension of the tongue of the voltagecore return-pathmember. The series-core of substantially U-shape has its innerextremities so that the series core-shunt is adapted to dove-tailtherein and secure the series-core laminations firmly. together.

' In order to comprehend my invention more thoroughly, reference may behad to the accompanying drawing, in which,

Fig. 1 is a side elevational view of a meter structure embodying myinvention Fig. 2 is a top plan view of the series-core shunt andseries-core shown in Fig. 1 and Fig. 3 is a top plan View of a miodifiedseries-core structure.

A voltage-core 1, having a central leg 2 and side members 3 and 4., hasa return-path mem- A series-core 7 ofU-shape, located under thevoltage-core member 1, has recesses 8 and 9 in its inside extremities. Atongue 10 of the voltage-core return-path member 5 is adapted to fitinto the recesses 8 and *9 to form a magnetic shunt for the series-core7. Screws 11 secure the extension of the tongue 10' to the series-coremagnet 7. Non-magnetic members 12 separate the magnetic shunt from theseries-core magnet 7.

The extension of the tongue 10 is forced into the recesses 8 and 9 insuch manner that the laminations of the core 7 are held firmly in place.Noises due to frequency variations are thus substantially avoided. Theseparatber 5 mounted thereon by means of screws 6.-

ing' members 12,.in a preferred form of my invention, are made of arelatively soft material, such as brass, into which the laminations willfit snugly.

In Fig. 3,*non-magnetic laminations 13, having inwardly projectingportions in the recesses 8 and 9, are provided in the middle portions ofthe laminated core 7; thus pro=- viding an air gap between the laminatedmembers of the core 7 and the tongue 10. when the latter is in position.

The laminations 13 are of the same shape as the laminated core 7, withthe exception of the recessed portions 8 and 9. These portions of thelaminations 13 are extended to fasten the tongue 10 rigidly to the corestructure 7. With such combination, the laminations of thecore 7 are notshort-circuited by the member 10, because an air gap is between it andthe core. Eddy-current losses are, in this manner, substantiallyreduced. The laminations 13 may be of magnetic material but I prefer toconstruct them of a non-magnetic material, in order to reduce losses bygven eliminating eddy-currents in these memers.

The structure shown in Fig. 3 is a refined embodiment of my inventionand may be necessary only where an extremely accurate meter is to bemanufactured.

The mass of the member 1 being different from the mass of the member 7,their fre quencies of vibration will be different. Fastening the tworigidly together in the manner shown causes their individualvibrationsto be damped. The combined structure vibrates with a considerably lowerfrequency than either of the separate members if uncombined, a conditionthat reduces bearing deterioration and frequency noises.

It will be understood that the magnetic shunt shown may be of any one ofvarious shapes and may be secured to the series core I in various waysother than those shown without departing from the spirit of myinvention, all modifications of which I desire to include in the scopeof the appended claims.

I claim as my invention:

1. In combination, in an induction meter, a voltage core comprisingthree projecting portions, a current coreof substantially U- shapehaving slots provided in the end portions thereof, and a magnetizablemember secured to the outer projecting portions of said voltage core andto the end portions of said current core in said slots, saidmagnetizable member between the'end portions of said current coreconstituting a shunt for improving the overload characteristic of themeter. 2. In combination, in an induction meter, a current corecomprising magneticand non, magnetic laminations,rand a shunt disposedbetween projecting portions of saidcore', said non-magnetic laminationsconstituting means for securing said shunt in position;

In s im ny hereof, hav hereunto sub.- ribed my nam at N remberg his 16day fNQYQmbQ T, 1.92.6- v f i ALBERT

